Method and device for imaging liquid-filling container

ABSTRACT

The present invention relates to a method and an apparatus for imaging a liquid-filling container in which a plurality of imaging devices each comprising a light emitting unit and a light receiving unit are provided. Light from each light emitting unit is irradiated onto a liquid-filling container and this light transmitted through the container is received by each light receiving unit. The object of the present invention is to provide such method and an apparatus for imaging a liquid-filling container. This method or apparatus allows for simultaneous and highly reliable imaging of two or more kinds of condition of the container. For accomplishing this object, according to the present invention, wavelengths of the lights emitted by the respective light emitting units and received by the respective light receiving units of the imaging devices for imaging the liquid-filling containers are different from each other.

BACKGROUND OF THE INVENTION

1. Filed of the Invention

The present invention relates to a method and an apparatus for imaging aliquid-filling container in which a plurality of imaging devices eachcomprising a light emitting unit and a light receiving unit are providedand light from each light emitting unit is irradiated onto aliquid-filling container and the light transmitted through the containeris received by each light receiving unit.

2. Description of Prior Art

The imaging of a liquid-filling container noted above is employed in amanufacturing line of various beverages such as soft drinks or alcoholicbeverages in order to inspect whether the amount of liquid as thebeverage filled in a container made of glass or PET is within apredetermined range or not and/or whether any foreign substance isinadvertently mixed in the beverage filled in the container or presentin the container or the material forming the container or a condition ofthe mouth of the liquid-filling container, or whether a cap is securelyfitted on the mouth of the container or not.

Conventionally, in the case of inspection of e.g. beverage by way ofimaging a liquid-filling container, a single light emitting unit emitsand irradiates a visible light having a wavelength of 400 to 700 nm ontothe container to be transmitted therethrough to be received by a lightreceiving unit comprising a CCD camera for imaging of the container, sothat the inspection is effected based on the image whether the surfacelevel of the liquid inside the container is within a predetermined rangeor not. And, another light emitting unit is employed for emitting avisible light of the same wavelength for determination as to whether anyforeign substance is mixed in the beverage or in the container or thematerial forming the container or not. And, still another light emittingunit is employed for emitting the visible light of the same wavelengthto be reflected by the mouth of the container or the cap and thisreflected light is received by a corresponding light receiving unit fordetermination as to the condition of the container mouth or whether thecap is properly fitted to this mouth or not.

With the conventional imaging technique above, the light emitting unitsfor the detection of the liquid surface level, the detection of theforeign substance present in the liquid or in the container or itsmaterial and the detection of the mouth or the attached condition of thecap to the mouth all emit a visible light of a same wavelength.Accordingly, e.g. irregular reflection of the light may occur due to theshape of the liquid-filling container to interfere as a noise with thevisible light for liquid surface level detection and the visible lightfor the cap attachment condition detection. So that, a portion of thevisible light for liquid level detection may enter the light receivingunit for cap attachment detection. Conversely, a portion of the visiblelight for foreign substance detection or cap attachment detection can beincident on the light receiving unit for the liquid level detection.Consequently, the detection of liquid surface level, the detection offoreign substance and detection of cap attachment can not be reliablyeffected simultaneously.

For improving the detection precision, it is conceivable to provide atime difference between the liquid level detection, foreign substancedetection and cap attachment detection, so as to effect the liquid leveldetection first and to effect the detection of foreign substance or capattachment thereafter. This, however, increases the time required fordetection, inviting reduction in the production efficiency.

Another conceivable method is to block the noise by changing orshielding the sites of detection between the liquid level detection andthe foreign substance or cap attachment detection. This, however,increases the space required for detection. In the case of amanufacturing line of beverage for instance, this method will make itdifficult to form the manufacturing line compact and will require muchcost in terms of maintenance and production efficiency.

The present invention has been devised to overcome the above-describedproblems of the prior art. A primary object of the invention is toprovide a method and an apparatus for imaging a liquid-filing containerwhich method or apparatus allows simultaneous and highly reliableimaging of two or more kinds of condition of the container.

SUMMARY OF THE INVENTION

According to the present invention, as shown in FIGS. 1 and 3 forexample, in a method and an apparatus for imaging a liquid-fillingcontainer in which a plurality of imaging devices 2, 5, 8, 20 eachcomprising a light emitting unit 3, 6, 9, 21 and a light receiving unit4, 7, 10, 22 are provided and light from each light emitting unit 3, 6,9, 21 is irradiated onto a liquid-filling container B and this lighttransmitted through the container is received by each light receivingunit 4, 7, 10, 22, wherein wavelengths of the lights emitted by therespective light emitting units 3, 6, 9, 21 and received by therespective light receiving units 4, 7, 10, 22 of the imaging devices 2,5, 8, 20 for imaging the liquid-filling containers are different fromeach other.

With this feature, a plurality of imaging devices each comprising alight emitting unit and a light receiving unit are provided andwavelengths of the lights emitted by the respective light emitting unitsand received by the respective light receiving units of the imagingdevices for imaging the liquid-filling containers are different fromeach other. Therefore, there occurs no such trouble as light irradiatedfrom one light emitting unit enters a light receiving unit notcorresponding to this light emitting unit. Consequently, two or morekinds of conditions of the liquid-filing container may be imagedsimultaneously and reliably.

According to the present invention, as shown in FIGS. 1 and 3 forexample, the light emitting units 3, 6, 9, 21 respectively have lightemitters 3A, 6A, 9A, 21A each capable of emitting and irradiating lightof a predetermined wavelength and the light receiving units 4, 7, 10, 22respectively have light-receiving cut filters 17, 18, 19, 24 forallowing transmission of a light in the predetermined wavelength andlight receivers 4A, 7A, 10A, 22A for receiving the light transmittedthrough the respective light-receiving cut filters 17, 18, 19, 24corresponding thereto.

With this feature, the light emitting units respectively have lightemitters each capable of emitting and irradiating a light in thepredetermined wavelength and the light receiving units respectively havelight-receiving cut filters for allowing transmission of light in thepredetermined wavelength and light receivers for receiving the lighttransmitted through the respective light-receiving cut filterscorresponding thereto. Therefore, there is no need of employing aspecial construction as the light receiving unit. As a result, theinvention may be embodied, with using a light emitter, a light receiverand a cut filter which are relatively inexpensive.

According to the present invention, as shown in FIGS. 1 and 3 forexample, at least one of said light emitting units 3, 6, 9, 21 emits andirradiates near infrared light.

According to the present invention, at least one of said light receivingunits 4, 7, 10, 22 receives near infrared light.

With these features, at least one of said light emitting units emits andirradiates near infrared light or at least one of said light receivingunits receives near infrared light. Therefore, it is possible to detecte.g. the filled amount of the liquid, regardless of the color of thecontainer or the color of the liquid filled inside the container.

Namely, in case the detection of the filled amount of the liquid orpresence/absence of any foreign substance in the liquid or in thecontainer or in the container forming material is effected by way ofimaging the liquid-filling container by using a visible light having awavelength of 400 nm to 700 nm as conventionally proposed, if thecontainer has a dark color such as black, dark green or dark brown, asshown in a graph of FIG. 4 (transmittance for a glass thickness of 3mm), the transmittance of the visible light becomes extremely low.

For this reason, when the visible light emitted from the light emittingunit is received by the light receiving unit, the portion of the visiblelight travelling outside the container is received substantially as itis or directly by the light receiving unit, so that the amount ofreceived light for this area outside the container is large, whereas theamount of light corresponding to the container is extremely small. Then,since the inspection of the liquid surface of the liquid filled in thecontainer or of the absence/presence of any foreign substance in theliquid or in the container or its material is to be effected for sucharea of extremely limited received light amount, the detection errorbecomes significant or the detection of the liquid surface or mixedforeign substance per se becomes very difficult. Further, even if theabsolute light amount is increased to overcome this problem, improvementin the detection precision made possible by such measure is limited.

Further, even if the container per se does not have such dark color asblack, dark green or dark brown, if the liquid filled therein has a darkcolor, the detection of foreign substance in the liquid becomesimpossible. Moreover, if fine bubbles generated in association with thefilling operation of the liquid are present near the liquid surface, theamount of light transmitted through the bubbles will be small due to theeffect of diffused reflection of the light by the bubbles and also theamount of light transmitted through the liquid portion too will belimited due to the dark color, so that discrimination therebetween isdifficult, thus impeding reliable detection of the liquid surface.

On the other hand, with the use of near infrared light having awavelength of 700 to 900 nm, preferably 750 to 850 nm, even if thecontainer has a dark color such as black, dark green or dark brown or ifthe filled liquid has a dark color or even if the container has asurface frosting treatment, there occurs no significant reduction in thetransmittance of the near infrared light through the liquid-fillingcontainer. So that, significant reduction in the received light amountfor the area corresponding to the liquid-filling container may beavoided advantageously.

Accordingly, various kinds of detection for the area corresponding tothis container of the liquid surface level or of any foreign substancepresent in the liquid or in the container or the container material aremade possible. As a result, the various conditions of the liquid-filingcontainer can be reliably detected, regardless of the color of thecontainer or the color of the liquid or regardless of presence/absenceof bubbles near the liquid surface.

Incidentally, for imaging a liquid-filling container by irradiatinglight from the light emitting unit onto the container and receiving thetransmitted light by the light receiving unit, or receiving the light bythe light receiving unit, according to the present invention, the amountof received light at the area corresponding to the container ispositively increased so as to reduce the difference in the receivedlight amounts relative to that of the area corresponding to the outsideof the container thereby to improve the detection precision. Byirradiating the near infrared light alone or a greater amount of nearinfrared light component than visible light component of the light, asufficient amount of near infrared light may be transmitted, dependingon the color of the container or the color of the liquid filled therein.Or, by receiving the near infrared light component alone or a greateramount of near infrared component than the visible light component bythe light receiving unit, a sufficient amount of near infrared light maybe transmitted, depending on the color of the container or the color ofthe liquid filled therein.

According to the present invention, as shown in FIGS. 1 and 3 forexample, each imaging device 2, 5, 8, 20 images a state of aliquid-filled container B which is conveyed one after another along atransport line 1.

With this characterizing, each imaging device images a state of aliquid-filled container which is conveyed one after another along atransport line. Therefore, for the number of liquid-filling containersbeing conveyed along the transport line one after another, variousconditions thereof such as the filled amount, presence/absence offoreign substance in the liquid, presence/absence of foreign substancein the container or the container forming material, and the condition ofthe container mouth or attachment condition of a cap to the containermouth can be detected speedily and continuously.

According to the present invention, as shown in FIG. 1 for example, inthe method of imaging a liquid-filling container or the apparatus forimaging a liquid-filling container, one of said plurality of imagingdevice 2, 5, 8 is a filled-amount detecting device 2 for detecting thefilled amount of liquid W filled in the container B.

With this feature, one of said plurality of imaging devices is afilled-amount detecting device for detecting the filled amount of liquidfilled in the container. Therefore, the filled amount of the liquidfilled in the liquid-filling container may be detected. Especially, ifnear infrared light is used in this filled-amount detecting device, forthe reasons described hereinbefore, even if the container has a darkcolor such as black, dark green or dark brown or if the filled liquidhas a dark color or even if the container has a surface frostingtreatment, the detection of liquid level is possible at the areacorresponding to this container. As a result, the filled amount of theliquid may be detected reliably, regardless of the color of theliquid-filling container or the liquid or presence/absence of bubblesnear the liquid surface.

According to the present invention, as shown in FIG. 1 for example, inthe method of imaging a liquid-filling container or the apparatus forimaging a liquid-filling container, one of said plurality of imagingdevices 2, 5, 8 is a liquid foreign substance detecting device 5 fordetecting foreign substance present in the liquid filled in thecontainer B.

With this feature, one of said plurality of imaging devices is a liquidforeign substance detecting device for detecting foreign substancepresent in the liquid filled in the container. Therefore, thepresence/absence of foreign substance in the liquid filled in theliquid-filling container may be detected. Especially, if near infraredlight is used in this liquid foreign substance detecting device, for thereasons described hereinbefore, even if the container has a dark colorsuch as black, dark green or dark brown or if the filled liquid has adark color or even if the container has a surface frosting treatment,the detection of the presence/absence of foreign substance in the liquidis possible at the area corresponding to this container. As a result,the presence/absence of foreign substance in the liquid may be detectedreliably, regardless of the color of the liquid-filling container or theliquid or presence/absence of bubbles near the liquid surface.

According to the present invention, as shown in FIG. 3 for example, inthe method of imaging a liquid-filling container or the apparatus forimaging a liquid-filling container, one of said plurality of imagingdevices 8, 20 is a container/container-material foreign substancedetecting device 20 for detecting foreign substance present in thecontainer or in material forming the container.

With this characterizing feature, one of said plurality of imagingdevices is a container/container-material foreign substance detectingdevice for detecting foreign substance present in the container or inmaterial forming the container. Therefore, the presence/absence offoreign substance in the liquid-filling container or in the materialforming the container may be detected. Especially, if near infraredlight is used in this container foreign substance detecting device, forthe reasons described hereinbefore, even if the container has a darkcolor such as black, dark green or dark brown or if the filled liquidhas a dark color or even if the container has a surface frostingtreatment, the detection of the presence/absence of foreign substance inthe container or in the container material is possible at the areacorresponding to this container. As a result, the presence/absence offoreign substance in the container or container material may be detectedreliably, regardless of the color of the liquid-filling container or theliquid.

According to the present invention, in the method of imaging aliquid-filling container or the apparatus for imaging a liquid-fillingcontainer, one of said plurality of imaging devices 2, 5, 8, 20 is acontainer mouth detecting device 8 for detecting condition of a mouth ofthe container B or attachment condition of a cap C to the containermouth.

With this characterizing feature, one of said plurality of imagingdevices is a container mouth detecting device for detecting condition ofa mouth of the container or attachment condition of a cap to thecontainer mouth. With this, needless to say, it is possible to detectcondition of a mouth of the container or attachment condition of a capto the container mouth by effectively utilizing the light reflected fromthe container mouth or from the cap. Moreover, even when thefilled-amount detecting device, the liquid foreign substance detectingdevice and the container/container-material foreign substance detectingdevice are used at one time together, there occurs no interferencetherebetween, and the condition of a mouth of the container orattachment condition of a cap to the container mouth may be detected.

Incidentally, in the above description, reference marks and numeralswere employed for facilitating reference to the accompanying drawings.It is understood that the provision of these marks and numerals is notto limit the invention to the constructions shown in the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing an apparatus for imaging aliquid-filling container relating to the invention,

FIG. 2 is a graph showing characteristics of a CCD camera,

FIG. 3 is a perspective view showing an apparatus for imaging aliquid-filing container relating to a further embodiment of theinvention, and

FIG. 4 is a graph showing transmittance of light.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of a method and an apparatus relating to thepresent invention for imaging a liquid-filling container will bedescribed next with reference to the accompanying drawings.

These method and apparatus for imaging a liquid-filling container arefor use in e.g., a manufacturing or bottling line of a bottled beveragesuch as soft drinks or alcoholic beverages, wherein the method or theapparatus is employed for inspecting whether the container or bottlefilled with beverage in the foregoing process contains a predeterminedfilled content of the beverage or not or whether any foreign substanceor object other than the beverage may be present inside the filledbottle or not, or whether any foreign matter or substance may be presentwithin the material forming the bottle or not, or whether any flaw ispresent at the mouth of the liquid-filling bottle or a cap is properlyattached to this mouth or not. Such manufacturing line, as shown in FIG.1, include a transfer conveyer 1 for conveying a plurality ofliquid-filled glass containers or bottles B one after another.

The transfer conveyer 1 conveys, to a predetermined position, eachliquid-filling container B which was filled, in the foregoing stage ofthe process, with beverage W as a liquid by an unillustrated fillingdevice and then fitted atop with a cap by an unillustrated cappingdevice. At an upper position across this conveyer 1 and in opposition toeach other, there are disposed a light emitting unit 3 and a lightreceiving unit 4 together constituting a filled-amount detecting device2 as one imaging device.

Downwardly of the filled-amount detecting device 2, there is provided aliquid foreign substance detecting device 5 as another imaging devicefor detecting foreign substance present in the beverage or liquid insidethe liquid-filling container B. And, a light emitting unit 6 and a lightreceiving unit 7 together constituting this liquid foreign substancedetecting device 5 for detection of foreign substance are also disposedin opposition to each other across the transfer conveyer 1.

At a further upper position of the transfer conveyer 1, there aredisposed a light emitting unit 9 and a light receiving unit 10 one afteranother along the conveying direction of the transfer conveyer 1, theunits 9, 10 together constituting a container mouth detecting device 8as still another imaging device for detecting attachment condition of acap C to the mouth of the liquid-fillng container B.

The light receiving unit 4 for detection of filled amount, the lightreceiving unit 7 for detection of liquid foreign substance and the lightreceiving unit 10 for detection of container mouth are all connected toa controller 11. So that, the light emitted from the light emitting unit3 for detection of filled amount is irradiated onto each liquid-fillingcontainer B to be transmitted therethrough to be then received by thelight receiving unit 4 for detection of filled amount and based on theinformation about this received light, determination is made by thecontroller 11 whether the filled amount of the beverage W in eachliquid-filling container B is within a predetermined range or not.

Also, the light emitted from the light emitting unit 6 for detection ofliquid foreign substance is irradiated onto each liquid-fillingcontainer B to be transmitted therethrough to be then received by thelight receiving unit 7 for detection of liquid foreign substance andbased on the information about this received light, determination ismade by the controller 11 whether any foreign substance is present inthe liquid adjacent the bottom of each liquid-filling container B ornot.

Further, the light emitted from the light emitting unit 9 for detectionof container mouth is irradiated onto each liquid-fillng container B tobe reflected therefrom to be then received by the light receiving unit10 for detection of container mouth and based on the information aboutthis received light, determination is made by the controller 11 whetherthe cap C is properly attached to the mouth of the liquid-fillingcontainer B or not.

The light emitting unit 3 for detection of filled amount comprises alight emitter 3A which includes a number of LED 3 a arranged in aplate-like format. Similarly, the light emitting unit 6 for detection ofliquid foreign substance comprises a light emitter 6A which includes anumber of LED 6 a arranged in a plate-like format. If necessary, on thefront side of each of these light emitters 3A, 6A, there may be provideda diffuser plate 14 formed of an acrylic plate of a milky white color inorder to assure uniform light irradiation.

Further, the light emitting unit 9 for detection of container mouth toocomprises a light emitter 9A which includes a number of LED 9 a arrangedin a plate-like format. In this case too, if necessary, there may beprovided a diffuser plate 16 formed of a milky white acrylic plate forassuring uniform light irradiation.

The light irradiated from the filled-amount detecting light emitter 3Ais a near infrared light having a wavelength of 700 nm to 800 nm. Thelight irradiated from the liquid foreign substance detecting lightemitter 6A is a near infrared light having a wavelength of 800 nm to 900nm.

The light irradiated from the container-mouth detecting light emitter 9Ais a visible light having a wavelength of 400 nm to 700 nm.

The filled-amount detecting light receiving unit 4 includes a lightreceiver 4A comprising e.g. a CCD camera and a light-receiving cutfilter 17 disposed on the front side of the light receiver 4A. The cutfilter 17 is provided as a filter adapted for selectively transmitting apredetermined wavelength alone, i.e. the near infrared light having awavelength shorter the range of 700 nm to 800 nm.

Similarly, the liquid foreign substance detecting light receiving unit 7includes a light receiver 7A comprising e.g. a CCD camera and alight-receiving cut filter 7B disposed on the front side of the lightreceiver 7A This cut filter 7B is provided as a filter adapted forselectively transmitting the near infrared light having a wavelengthshorter than the range of 800 nm to 900 nm alone.

Further, the container mouth detecting light receiving unit 10 includesa light receiver 10A comprising e.g. a CCD camera and a light-receivingcut filter 19 disposed on the front side of the light receiver 10A. Thiscut filter 19 is provided as a cut filter adapted for selectivelytransmitting the visible light having a wavelength shorter than therange of 400 nm to 700 nm alone.

Incidentally, as shown in a graph in FIG. 2, such CCD camera exhibits alower relative sensitivity for the near infrared radiation range thanfor the visible light range. However, any CCD cameras can be employed aslong as their wavelength ranges between 700 nm and 900 nm.

According to this embodiment, onto each liquid-filing container Bconveyed on the transfer conveyer 1, the filled-amount detecting lightemitting unit 3 emits and irradiates the near infrared light having awavelength of 700 nm to 800 nm alone, the liquid foreign substancedetecting light emitting unit 6 emits and irradiates the furtherinfrared light having a wavelength of 800 nm to 900 nm alone and thecontainer mouth detecting light emitting unit 9 emits and irradiates thevisible light having a wavelength of 400 nm to 700 nm alone,respectively and simultaneously.

The near infrared light from the filled-amount detecting light emittingunit 3 and the further near infrared light from the liquid foreignsubstance detecting light emitting unit 6 are transmitted through theliquid-fillng container B to be received by the filled-amount detectinglight receiving unit 4 and the liquid foreign substance detecting lightreceiving unit 7, respectively. Further, the visible light from thecontainer mouth detecting light emitting unit 9 is reflected by the capC to be received by the container mouth detecting light receiving unit10.

Then, the information of these lights received respectively by the threelight receiving units 4, 7, 10 are sent to the controller 11, so thatthis controller 11 determines the filled amount of the beverage W in theliquid-filling container B based on the received light information fromthe filled-amount detecting light receiving unit 4, i.e. whether theliquid level of the beverage W is within a predetermined range or notand determines also presence/absence of any foreign substance in theliquid, i.e. beverage in the liquid-filling container B based on thereceived light information from the liquid foreign substance detectinglight receiving unit 7 and the controller further determines whether thecap C is properly attached to the mount of the container B or not, basedon the received light information from the container mouth detectinglight receiving unit 10.

If any liquid-filling container B is detected to contain more than thepredetermined range of beverage W or any foreign substance mixed in thebeverage W or have improper attachment of the cap C, then, a certainappropriate measure will be taken, such as automatic removal of thisliquid-filling container B away from the conveyer 1 or issuance of analarm by means of an alarming device.

[Other Embodiments]

(1) In the foregoing embodiment, three detecting devices of thefilled-amount detecting device 2, the liquid foreign substance detectingdevice 5 and the container mouth detecting device 8 are provided.Instead, the present invention may be embodied with providing two ofthem, i.e. the filled-amount detecting device 2 and the liquid foreignsubstance detecting device 5 alone or the filled-amount detecting device2 and the container mouth detecting device 8 alone or the liquid foreignsubstance detecting device 5 and the container mouth detecting device 8alone.

Further alternately, the invention may be embodied also with providing afurther detecting device other than the filled-amount detecting device 2and the liquid foreign substance detecting device 5. An example of suchmodified embodiment is illustrated in FIG. 3.

Next, this modified embodiment will be described with reference to FIG.3. In the following description, in order to avoid redundancy ofdescription, the same components and components having the same functionas those employed are denoted with identical reference marks or numeralsand description of them will be omitted. The following descriptionconcerns mainly those portions different from the foregoing embodimentonly.

In this further embodiment, in place of the filled-amount detectingdevice 2 and the liquid foreign substance detecting device 5, there isprovided a container/container-material foreign substance detectingdevice 20 as an imaging device for detecting whether any foreignsubstance was inadvertently mixed in the material forming eachliquid-filling container B during the previous stage of manufacture.This container/container-material foreign substance detecting device 20similarly includes a light emitting unit 21 and a light receiving unit22 which are disposed in opposition to each other across the transferconveyer 1.

The light emitting unit 21 comprises a light emitter 21A which includesa number of LED 21 a arranged in a plate-like format. The irradiatedlight from this light emitter 21A is a near infrared light having awavelength of 700 to 900 nm. The light receiving unit 22 includes alight receiver 22A comprising a CCD camera and a light-receiving cutfilter 24 disposed on the front side of the light receiver 22A. This cutfilter 24 is provided as a filter adapted for selecting transmitting thenear infrared light having a wavelength of 700 to 900 nm alone.

Therefore, according to this further embodiment, for each liquid-fillingcontainer B conveyed by the transfer conveyer 1, the light emitting unit21 for detection of foreign substance in the container material emitsand irradiates the near infrared light having a wavelength of 700 to 900nm and the container mouth detecting light emitting unit 9 emits andirradiates the visible light having a wavelength of 400 to 700 nm,respectively and simultaneously. And, the near infrared light from thecontainer/container-material foreign substance detecting light emittingunit 21 is transmitted through the liquid-filling container B to bereceived by the light receiving unit 22 corresponding thereto, while thevisible light from the container mouth detecting light emitting unit 9is reflected by the cap C to be received by the light receiving unit 10corresponding thereto.

Thereafter, like the foregoing embodiment, the controller 11 effectsdetermination about presence/absence of foreign substance mixed in thematerial forming the liquid-filling container B, based on the receivedlight information from the container/container-material foreignsubstance detecting light receiving unit 22 and also determination as towhether the cap C is properly attached or not, based on the receivedlight information from the container mouth detecting light receivingunit 10, respectively. Then, based on the results of thesedeterminations, some appropriate measure will be taken.

Incidentally, in this modified embodiment shown in FIG. 3, thecontainer/container-material foreign substance detecting device 20 picksout the entire image of the liquid-filling container B. Therefore, basedon the received light information from this container/container-materialforeign substance detecting device 20, the controller 11 can be modifiedto detect not only presence/absence of foreign substance in thecontainer B material, but also other conditions as well at the sametime.

That is to say, by using the apparatus having the construction of FIG. 3as it is, it is possible to adapt the single detecting device 20 todetect both the presence/absence of foreign substance in the materialforming the liquid-filling container B and the presence/absence offoreign substance in the liquid or to detect both the presence/absenceof foreign substance in the material forming the liquid-fillingcontainer B and the filled amount or both the presence/absence offoreign substance in the liquid and the filled amount.

Moreover, by using the apparatus having the construction of FIG. 3 as itis, it is also possible to detect the presence/absence of foreignsubstance in the material forming the liquid-filling container B and thepresence/absence of foreign substance in the liquid-filling container Bindividually or simultaneously with detection of the condition of themouth of the liquid-filling container B.

That is to say, in the embodiment of FIG. 3, various conditions aredetected for each liquid-filling container B which was filled with thebeverage W and fitted with the cap C. Instead, the construction may beused also in a system in which a plurality of empty liquid-fillingcontainers having no beverage W filled therein and no caps C attachedthereto are conveyed in succession by the transfer conveyer 1.

In adopting such construction, for instance, the near infrared lightfrom the foreign substance detecting light emitting unit 21 istransmitted through the empty container B to be received by the foreignsubstance detecting light receiving unit 22 for detection of any foreignsubstance in the material forming the liquid-filling container B andfurther detection of foreign substance inside the container B. Thus, byusing such foreign substance detecting device 20 shown in FIG. 3, thedetection of presence/absence of foreign substance in the material ofthe liquid-filling container B and the further detection ofpresence/absence of foreign substance inside the liquid-fillingcontainer may be effected individually or simultaneously. For thisreason, this foreign substance detecting device 20 is genericallyreferred to as a “container/container-material foreign substancedetecting device”.

Further, the visible light from the container mouth detecting lightemitting unit 9 is reflected by the mouth of the empty liquid-fillingcontainer B to be received by the container mouth detecting lightreceiving unit 10 for detection of presence/absence of a nick, flaw orstain at the mouth of the empty container B.

(2) In the foregoing embodiments, each of the light receivers 3A, 6A,9A, 21A is constituted from a number of LED 3 a, 6 a, 9 a, 21 a arrangedin a plate-like format. Instead, it is also possible to adapt the lightemitter to emit only a light of a predetermined wavelength, by e.g.forming the unit of a near-infrared light emitting diode.

Moreover, the light emitting unit may include a light emitter elementhaving a wide range of wavelength, such as a conventional incandescentelectric lamp, a fluorescent lamp, a stroboscopic lamp, etc. Then, if adiffuser plate is provided on the front side of this light emitter, alight-emitter cut filter for selective transmission of a predeterminedwavelength light component may be provided in front of or behind thediffuser plate.

(3) In case the filled-amount detecting light emitter 3A and the liquidforeign substance detecting light emitter 6A are provided like the aboveembodiment, these two light emitters 3A, 6A may be provided as a singleintegrated unit. That is, a single light emitter for emitting lighthaving a wide range of wavelength is provided and a light-emitting cutfilter for selective transmission of the near infrared light having awavelength shorter than the range of 700 nm to 800 nm alone is providedupwardly of and on the front side of the emitter, so as to provide afilled-amount detecting light emitter 3A together. Further, downwardlythereof, another light-emitting cut filter 13 for selective transmissionof the near infrared light having a wavelength of 800 nm to 900 nm aloneis provided to constitute the liquid foreign substance detecting lightemitter 6A.

(4) In the foregoing embodiments described above, a glass bottle is usedas an example of the liquid-filling container B. The invention is notlimited thereto. The invention may find utility also for other types ofcontainers or bottles made of other material such as a synthetic resin,exemplified by a PET bottle. Also, in this invention, the type of liquidW is not particularly limited to the beverage. The invention is usefullfor any other kind of liquid than beverages.

Further, the foregoing description concerns a construction for use in amanufacturing line for successively filling a plurality ofliquid-filling containers B being conveyed one after another. Instead,the invention may find utility also in a construction in which thefilled amount in the container B, the presence/absence of foreignsubstance in the liquid, inside the container or in the containermaterial and the attachment condition of the cap are detectedindividually for each liquid-filling container B filled with the liquidW. Further, the invention may find utility also in a construction thepresence/absence of foreign substance in the container or the containermaterial, the condition of the container mouth etc. are detectedindividually for each empty liquid-filing container B.

(5) In the foregoing embodiments, the light emitting units 3, 6, 21irradiate near infrared lights and the light receiving units 4, 7, 22receive these near infrared lights. Instead, it is also possible toadapt the light emitting units 3, 6, 21 to respectively irradiate alight containing a greater amount of infrared light component thanvisible light component and/or to adapt the light receiving units 4, 7,22 to receive a light containing a greater amount of infrared lightcomponent than visible light component.

INDUSTRIAL APPLICABILITY OF THE INVENTION

As described above, the method and apparatus of the invention forimaging a liquid-filled container is suitable, in particular, for amanufacturing line of various beverages such as soft drinks or alcoholicbeverages in order to inspect whether the amount of liquid as thebeverage filled in the container is within a predetermined range or notand/or whether any foreign substance is inadvertently mixed in thebeverage filled in the container or present in the container or thematerial forming the container or the condition of the mouth of thecontainer or whether a cap is securely fitted on the mouth of thecontainer or not.

What is claimed is:
 1. A method of imaging a liquid-filling containerwith a plurality of imaging devices, each imaging device including alight emitting unit and a light receiving unit, comprising the steps of:a) irradiating light from each light emitting unit onto theliquid-filling container; and b) receiving at each light receiving unitthe light transmitted through or reflected from the liquid-fillingcontainer, wherein said plurality of imaging devices differ from eachother in optical axes and wavelengths of the lights irradiated by therespective light emitting units and received by the respective lightreceiving units corresponding thereto; and said plurality of imagingdevices are used for different detection purposes associated with saidliquid-filling container.
 2. The method of claim 1, wherein said lightemitting units respectively have light emitters each capable of emittingand irradiating light of a predetermined wavelength and the lightreceiving units respectively have light-receiving cut filters forallowing transmission of a light in the predetermined wavelength andlight receivers for receiving the light transmitted through therespective light-receiving cut filters corresponding thereto.
 3. Themethod of claim 1, wherein at least one of said light emitting unitsemits and irradiates near infrared light.
 4. The method of claim 1,wherein at least one of said light receiving units receives nearinfrared light.
 5. The method of claim 1, wherein each of the pluralityof imaging devices images a state of liquid-filling containers which areconveyed one after another along a conveying line.
 6. The method ofclaim 1, wherein one of said plurality of imaging devices is afilled-amount detecting device for detecting the filled amount of theliquid filled in the container.
 7. The method of claim 1, wherein one ofsaid plurality of imaging devices is a liquid foreign substancedetecting device for detecting foreign substance present in the liquidfilled in the container.
 8. The method of claim 1, wherein one of saidplurality of imaging devices is a container/container material foreignsubstance detecting device for detecting foreign substance present inthe container or in material forming the container.
 9. The method ofclaim 1, wherein one of said plurality of imaging devices is acontainer-mouth detecting device for detecting condition of a mouth ofthe container or attachment condition of a cap to the container mouth.10. The method of claim 1, wherein each said light emitting unitcomprises a light emitter including a number of LEDs arranged in aplate-like format.
 11. An apparatus for imaging a liquid-fillingcontainer comprising a plurality of imaging devices, each imaging deviceincluding a light emitting unit and a light receiving unit, theapparatus irradiating light from each light emitting unit onto theliquid-filling container and receiving at each light receiving unit thelight transmitted through or reflected from the liquid-fillingcontainer, wherein said plurality of imaging devices differ from eachother in optical axes and wavelengths of the lights irradiated by therespective light emitting units and received by the respective lightreceiving units corresponding thereto; and said plurality of imagingdevices are used for different detection purposes associated with saidliquid-filling container.
 12. The apparatus of claim 11, wherein saidlight emitting units respectively have light emitters each capable ofemitting and irradiating light of a predetermined wavelength and thelight receiving units respectively have light-receiving cut filters forallowing transmission of a light in the predetermined wavelength andlight receivers for receiving the light transmitted through therespective light-receiving cut filters corresponding thereto.
 13. Theapparatus of claim 11, wherein at least one of said light emitting unitsemits and irradiates near infrared light.
 14. The apparatus of claim 11,wherein at least one of said light receiving units receives nearinfrared light.
 15. The apparatus of claim 11, wherein each of theplurality of imaging device images a state of each of liquid-fillingcontainers which are conveyed one after another along a conveying line.16. The apparatus of claim 11, wherein one of said plurality of imagingdevices is a filled-amount detecting device for detecting the filledamount of the liquid filled in the container.
 17. The apparatus of claim11, wherein one of said plurality of imaging devices is a liquid foreignsubstance detecting device for detecting foreign substance present inthe liquid filled in the container.
 18. The apparatus of claim 11,wherein one of said plurality of imaging devices is acontainer/container material foreign substance detecting device fordetecting foreign substance present in the container or in materialforming the container.
 19. The apparatus of to claim 11, wherein one ofsaid plurality of imaging devices is a container-mouth detecting devicefor detecting condition of a mouth of the container or attachmentcondition of a cap to the container mouth.
 20. The apparatus of claim11, wherein each said light emitting unit comprises a light emitterincluding a number of LEDs arranged in a plate-like format.